It is well documented that wood fumigants have improved safety, reliability, and longevity of wood structures exposed to the environment.
Trichloronitromethane (also known by the proprietary names chloropicrin, timberfume, timberfume II, chloropicrin 100, and Chloro-Pic) has been proven through research and commercial practice to be an effective and long lasting fumigant used for controlling internal deterioration of wood structures since the mid-1960s. However, it has not gained wide acceptance for general use.
Trichloronitromethane has been used within electrical utility poles, railroad trestles, roadway bridges, beams, and timbers in wood buildings. Although it is registered with the U.S. Environmental Protection Agency (EPA) for this use in wood, there has been a reluctance to use it because of its strong lacrimation property. This property also makes it useful as a tear gas in crowd control and a warning agent incorporated into dangerous odorless gases used for house fumigation. Many utilities and contractors in the past have chosen to use less effective supplemental wood treatments that are easier to apply.
To prolong the life of wood members, holes are drilled into the member, a wood-treatment agent is then inserted into the holes, and the holes are sealed. It is common for the holes to be sealed using a piece of wood dowel or a plastic plug.